PONGO 195 
Simia bicolor I. Geoff., Archiv. Mus. Hist. Nat., Paris, II, 1841, 
p. 526; Id. Cat. Primates, 1851, p. 6; Reichenb., Vollstand. 
Naturg. Affen, 1862, p. 182, figs. 455-457, t. 33, fig. 497. 
Simia satyrus (nec Linn.), Gray, Cat. Monkeys, Lemurs and 
Fruit-eating Bats, Brit. Mus., 1870, p. 8. 
Pithecus sumatranus deliensis Selenka, Sitzungsb. Akad. Wiss., 
Berlin, XVI, 1896, p. 386. 
Pithecus sumatranus obogensis Selenka, Sitzungsb. Akad. Wiss., 
Berlin, XVI, 1896, p. 386. 
Pongo pygmeus bicolor Rothsch., Proc. Zool. Soc. Lond., II, 1904, 
pp. 437, 439. 
Pongo pygmeus abelu Rothsch., Proc. Zool. Soc. Lond., II, 1904, 
pp. 437, 439. 
Type locality. Ramboom, near Touraman. N. W. coast of 
Sumatra. 
Geogr. Distr. Borneo and Sumatra. 
Genl. Char. Uair dark mahogany to fox red, and frequently 
with patches of ochraceous. 
The above is the synonymy, or the essential citations of the Bor- 
nean and Sumatran Ourang-utans, and while of the opinion that there 
is only one species of this great Ape, I have not been able to compare 
sufficient material from the two islands to enable me to give a decided 
opinion as to their identity. I can only state that I have been unable 
to discover any character that would indicate they were distinct. The 
crania of the Sumatran Ourang that I have seen, present the same 
great individual variations that are so conspicuous in the Bornean 
examples, and afford no character upon which to base a specific 
difference from the Bornean Ourang or from among themselves, and 
the color of the pelage exhibits much variation among specimens. I 
have kept the synonymy separate in order to show what name each 
would bear, should ample material, gathered in the future, prove they 
were entitled to be considered distinct, which cannot be shown at the 
present time. 
The following dimensions are taken from a Landak skull from 
Upper Merekai River, Landak-Sarawak District, Borneo: 
Measurements. Skull adult male, total length, 240; occipito-nasal 
length, 167; intertemporal width, 59; breadth of braincase, 103; Hen- 
sel, 182; zygomatic width, 174; extreme breadth of orbits, 112; width 
of rostrum at canines, 77; palatal length, 93; length of upper canines, 
33.6; length of upper molar series, 57.4; length of mandible, 184; 
